Amount of current and voltage in an average shock from a door nob?

AI Thread Summary
The average shock from a doorknob can reach voltages of at least a couple of kilovolts, with peak currents potentially in the hundreds of amps, but the duration is extremely brief, around one nanosecond. This transient nature means that while the current felt can be significant, the energy delivered is relatively low, typically around 7.5 millijoules for a 10kV discharge. Most people experience static shocks in the kilovolt range, which are not usually harmful. However, the sensation can be uncomfortable, and higher voltages, especially from arm-to-arm discharges, can be alarming. Overall, while static shocks can be startling, they are generally not dangerous due to their short duration and low energy.
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Amount of current and voltage in an average "shock" from a door nob?

What is the amount of current and voltage in an average "shock" from a door nob/handle? I have looked everywhere and cannot seem to find it! Please help!
Thanks
 
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wushumaster said:
What is the amount of current and voltage in an average "shock" from a door nob/handle? I have looked everywhere and cannot seem to find it! Please help!
Thanks

The common ESD test standard is EN 61000-4-2, and the test devices that you use to zap the equipment under test (to be sure they will be reliable in the real world) use an output circuit of 150pF in series with a 330 Ohm output resistor for air discharge testing. The rise time of the output discharge is on the order of 1ns.

For you to feel the shock, it would need to be at least a couple of kV. The peak currents are high (a couple hundred amps I think but I'm not sure about that), but the duration is so small that there is not much energy behind it. 10kV stored on 150pF is only 7.5mJ.
 


But we typically feel at least a small shock, right? So since current dominated what we "feel" are you saying that we would feel 100s of mA? Because I thought that kind of current has the potential to kill us. Electrical muscle stimulation max current is only 64 mA.
I'm trying to put in perspective for the IRB that the shock from EMS is not that big/ bad...
 


wushumaster said:
But we typically feel at least a small shock, right? So since current dominated what we "feel" are you saying that we would feel 100s of mA? Because I thought that kind of current has the potential to kill us. Electrical muscle stimulation max current is only 64 mA.
I'm trying to put in perspective for the IRB that the shock from EMS is not that big/ bad...

But as I said, this transient current only lasts for about a nanosecond. That's the difference.

Still, I've managed to shock myself accidentally during product ESD testing, and it's no fun at all. And I've accidentally taken about a 10kV air discharge from arm-to-arm (the worst way), and I could feel my heart not appreciating it at all. Luckily, most static shocks that you feel in normal life are just a kV or two, and not typically arm-to-arm.
 
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